![<?echo $_SERVER['SERVER_NAME'];?>](/template/twentyseventeen/skin/images/header.jpg)
The test was carried out on a 34252676 type CNC double action extruder. According to the shape, size and material of the part, a reasonable mold structure is designed, which is mainly composed of the lower punch, the lower concave die, the upper concave die and the upper punch 6; the modeling of the die is completed by using the three-dimensional modeling software for use in CNC machining.
The working process of the bevel gear cold precision forging frame is: the softened annealing blank is placed into the cold precision forging die. Then, the outer slider of the extruder is pressed down to close the upper mold and the lower mold, and a clamping force is applied to form a closed cavity. Then, the inner slider of the extruder is pressed down, and the upper punch is pushed down to make the blank flow plastically and fill the entire cavity. After the die forging is completed, the upper die is returned with the press slider, and the forging is pushed out by the lower punch.
Test results Analysis of the influence of process parameters on forming The forming process has many influencing factors on the forming. During the test, the cold-forging “octahedron technology†proposed by Japan Honda Co., Ltd. was verified, that is, to ensure normal production, the design and process of cold forging must be guaranteed. Design, mold design, mold manufacturing, blank lubrication, cold forging equipment, self-forging equipment and manufacturing technology, the first phase of the dynamic equipment and post-processing, etc., are indispensable. However, in the production practice, the original size and original shape of the two "face" blanks must also be added.
The design of cold forgings is the design of forgings, which can be well determined according to the design criteria of forgings and the degree of plastic deformation of the materials. The process is based on existing equipment conditions and reference empirical data. Mold design and manufacturing are more critical, especially in the manufacture of molds. High-speed milling has obvious advantages over EDM. High precision and easy metal flow. The blank lubrication can obtain deformation conditions suitable for plastic flow, reduce mold load, reduce wear and prolong the service life of the mold, and use the phosphorus saponification for the lubrication of the blank. The selection of cold forging equipment must be able to meet the tonnage requirements of cold forging and the matching of automatic equipment, and can realize the automatic control of cold forging, which is beneficial to the filling of forgings and improving the life of the mould. Post-processing is mainly processing such as machining that meets product requirements.
Precision forging requires precision blanks, so the original size and original shape of the blank is critical during the forming process. The original size of the blank can be determined according to the principle that the forging volume is equal: too large, waste material reduces the life of the mold; small, the forging can not be filled. Two shapes of blanks were tested: at the time a cylindrical blank, the clamping force and the final forming force were increased to and during the forming process, respectively. When the toothed portion of the lower die is not completely filled, the cold forged forging cannot meet the size requirement, and the plastic forging is close to the limit, and the cold forging has defects; when the blank shape of 012 is used, When the clamping force is reached and the final forming force is the same, the toothed portion in the lower die can be completely filled to meet the dimensional requirements of the cold forging. Due to the change in the shape of the blank, the flow effect of the metal is remarkably improved, the cold forging has no defects, and the problem of positioning of the blank in the toothed die is solved. The relationship between mold structure and forming is due to the large deformation force of cold forging, the large unit pressure of the die, and the large elastic deformation of the die. Therefore, the prestressed structure is needed to improve the bearing capacity and elasticity of the die. Deformation. In the test, according to the mold and blank material and the dimensional tolerance range, the compensation correction design of the cold precision forging die tooth shape is given.
The punch structure has an important influence on the forming. The simulation results of the computer forming process guide the test, and the ratio of the depth of the upper and lower punches pressed into the forging is about 3, so that the metal can effectively generate radial flow and facilitate the filling of the top. In addition, the stress state of the punch is the worst. Therefore, when designing the punch structure, the strength must be ensured. Pay special attention to the sharp corner portion that can cause stress concentration. The arc should be smoothly transitioned. In addition, the production should be considered. The head is easy to replace.
In the design of the mold 1, the position of the parting surface should be selected at the maximum diameter, but can still be appropriately adjusted. For example, 4 shows two different positions, namely 565 and 767 parting surfaces. The test found that the position of the parting surface has little effect on the forming force. However, with 565 as the die of the split surface, the contact surface of the toothed portion and the die in the die is larger than the split surface of 767. Therefore, the tooth can withstand a large bending strength and can withstand a large The stress, therefore, contributes to the improvement of mold life.
The gear sample analysis uses a 012-shaped blank. When the 767 is used as the parting surface, the required clamping force and final forming force are large, and sometimes the pinching phenomenon (0) occurs. With 565 as the parting surface, when the clamping force is , and the forming force is , the bevel gear parts that meet the requirements can be obtained, and the forming process is as shown.
Conclusion The car bevel gear is an important transmission component in the car, which requires high dimensional accuracy, surface quality and comprehensive mechanical properties. Because the cold precision forging technology has the advantages of precision, high quality, high efficiency, low cost, suitable for mass production, etc., it can meet the requirements well and become the mainstream technology for precision forging of complex toothed parts.
Coating Machine,Lamination Coating Machine,Multi-Purpose Coating Machine
Recycling Machine,Film Machine Co., Ltd. , http://www.nsfilmmachine.com